Re: (ITS#8493) Under heavy modrdn load, masters desync

[quanah@zimbra.com]

--On Saturday, September 03, 2016 6:15 AM +0000 quanah@openldap.org wrote:

> Full_Name: Quanah Gibson-Mount
> Version: 2.4.44+ITS8432
> OS: Linux 2.6
> URL: ftp://ftp.openldap.org/incoming/
> Submission from: (NULL) (75.111.52.177)
>
>
> Trying to reproduce another ITS, I discovered a new bug.  When doing
> MODRDN ops on one master, the other master keeps going out of sync.
> Specifically:
>
> Sep  3 01:12:17 zre-ldap002 slapd[29206]: syncrepl_message_to_op: rid=100
> be_modrdn uid=user.924,ou=people,dc=zre-ldap002,dc=eng,dc=zimbra,dc=com
> (32) Sep  3 01:12:17 zre-ldap002 slapd[29206]: do_syncrep2: rid=100
> delta-sync lost sync on (reqStart=20160903051215.747829Z,cn=accesslog),
> switching to REFRESH


Note that this master also has a replica.  The replica never rejected a 
single one of these MODRDNs coming from this master.  Which means that 
either:

a) The data on the master spontaneously corrupted at some point

or

b) The master wrote the MODRDNs to the accesslog, which the replica picked 
up, but did not itself make the MODRDN changes to its database.

In the end, of the 50,000 MODRDNs it was processing, it threw an error 32 
for 441 of them.

--Quanah



--

Quanah Gibson-Mount